From: Eric Botcazou <ebotcazou@gcc.gnu.org>
Date: Thu, 23 Apr 2020 20:25:04 +0000 (+0200)
Subject: Fix segfault with -O2 -fnon-call-exceptions -ftracer
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=cb76fcd7fb4a4f1e4d1688deca87969124f16fef;p=gcc.git

Fix segfault with -O2 -fnon-call-exceptions -ftracer

The GIMPLE SSA store merging pass blows up when it is rewriting the
stores because it didn't realize that they don't belong to the same
EH region.  Fixed by refusing to merge them.

	PR tree-optimization/94717
	* gimple-ssa-store-merging.c (try_coalesce_bswap): Return false if
	one of the stores doesn't have the same landing pad number as the
	first.
	(coalesce_immediate_stores): Do not try to coalesce the store using
	bswap if it doesn't have the same landing pad number as the first.
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e58d040e04d..e8d397a3713 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2019-04-23  Eric Botcazou  <ebotcazou@adacore.com>
+
+	PR tree-optimization/94717
+	* gimple-ssa-store-merging.c (try_coalesce_bswap): Return false if one
+	of the stores doesn't have the same landing pad number as the first.
+	(coalesce_immediate_stores): Do not try to coalesce the store using
+	bswap if it doesn't have the same landing pad number as the first.
+
 2020-04-23  Bill Schmidt  <wschmidt@linux.ibm.com>
 
 	* gcc/doc/extend.texi (PowerPC AltiVec/VSX Built-in Functions):
diff --git a/gcc/gimple-ssa-store-merging.c b/gcc/gimple-ssa-store-merging.c
index a6687cd9c98..25753517cc6 100644
--- a/gcc/gimple-ssa-store-merging.c
+++ b/gcc/gimple-ssa-store-merging.c
@@ -2435,6 +2435,7 @@ imm_store_chain_info::try_coalesce_bswap (merged_store_group *merged_store,
   for (unsigned int i = first + 1; i < len; ++i)
     {
       if (m_store_info[i]->bitpos != m_store_info[first]->bitpos + width
+	  || m_store_info[i]->lp_nr != merged_store->lp_nr
 	  || m_store_info[i]->ins_stmt == NULL)
 	return false;
       width += m_store_info[i]->bitsize;
@@ -2682,6 +2683,7 @@ imm_store_chain_info::coalesce_immediate_stores ()
       if (info->bitpos == merged_store->start + merged_store->width
 	  && merged_store->stores.length () == 1
 	  && merged_store->stores[0]->ins_stmt != NULL
+	  && info->lp_nr == merged_store->lp_nr
 	  && info->ins_stmt != NULL)
 	{
 	  unsigned int try_size;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 249a1520581..f9ab061922e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2019-04-23  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* g++.dg/opt/store-merging-4.C: New test.
+
 2020-04-23 Iain Sandoe <iain@sandoe.co.uk>
 
 	PR c++/94288
diff --git a/gcc/testsuite/g++.dg/opt/store-merging-4.C b/gcc/testsuite/g++.dg/opt/store-merging-4.C
new file mode 100644
index 00000000000..8a51dcd4c06
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/store-merging-4.C
@@ -0,0 +1,29 @@
+// PR tree-optimization/94717
+// Reported by Zdenek Sojka <zsojka@seznam.cz>
+
+// { dg-do compile }
+// { dg-options "-O2 -fnon-call-exceptions -ftracer" }
+
+int abs (int);
+
+static inline void
+bar (int d)
+{
+  d && abs (d);
+}
+
+struct S
+{
+  int a;
+  int b;
+  int c;
+  S (unsigned a, unsigned b) : a (a), b (b) { }
+};
+
+void
+foo (S *x)
+{
+  bar (x->c);
+  new S (x->a, x->b);
+  bar (0);
+}